Intelligent transport systems - eSafety - eCall High level application protocols (HLAP) using IP Multimedia Subsystem (IMS) over packet switched networks

In respect of pan European eCall (operating requirements defined in EN 16072), this document defines the high level application protocols, procedures and processes required to provide the eCall service via a packet switched wireless communications network using IMS (IP Multimedia Subsystem) and wireless access (such as LTE, NR and their successors). This document assumes support of eCall using IMS over packet switched networks by an IVS and a PSAP and further assumes that all PLMNs available to an IVS at the time an eCall or test eCall is initiated are packet switched networks. Support of eCall where eCall using IMS over packet switched networks is not supported by an IVS or PSAP or PLMN is out of scope of this document. At some moment in time packet switched networks will be the only Public Land Mobile Networks (PLMN) available. However as long as GSM/UMTS PLMNs are available (Teleservice 12/TS12) ETSI TS 122 003 will remain operational. Both the use of such PLMNs and the logic behind choosing the appropriate network in a hybrid situation (where both packet-switched and circuit-switched networks are available) are out of scope of this document.